QuakeIndex

Earthquake · reviewed by a seismologist

M 3.6mw

10km ESE of Hidden Valley Lake, CA

· 10 km deep · released about 3.8 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Napa County 31 kmLake County 45 kmYolo County 49 kmColusa County 49 kmSonoma County 49 kmSutter County 71 kmSolano County 72 kmMarin County 84 kmGlenn County 92 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 3.6 (mw)
Depth
10 km below the surface
Felt
77 reports · strongest reported intensity III
Measured shaking
intensity V (ShakeMap)
Nearest
Napa County, 31 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2515 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 77 people have reported feeling it to USGS.

How big was it?

This earthquake released about 3.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 45,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,400× the energy of this one
  4. This earthquake M 3.6 about 3.8 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 7.9× more

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

Where

Epicentre 38.7718, -122.4518. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 31 km (20 mi) NNW of here earthquakes near Napa County
Lake County, CA 45 km (28 mi) SE of here earthquakes near Lake County
Yolo County, CA 49 km (30 mi) WNW of here earthquakes near Yolo County
Colusa County, CA 49 km (30 mi) SSW of here earthquakes near Colusa County
Sonoma County, CA 49 km (31 mi) NE of here earthquakes near Sonoma County
Sutter County, CA 71 km (44 mi) WSW of here earthquakes near Sutter County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

59 earthquakes have been recorded within 50 km since this one.

  1. 2.8 9km WNW of Cobb, CA
  2. 2.0 7km NW of The Geysers, CA
  3. 1.5 6km WNW of The Geysers, CA
  4. 1.6 3km NW of The Geysers, CA
  5. 1.6 7km NW of The Geysers, CA
  6. 1.9 10km NW of Cobb, CA
  7. 1.7 7km NW of The Geysers, CA
  8. 2.0 6km NW of The Geysers, CA
  9. 1.5 7km NW of The Geysers, CA
  10. 1.7 4km W of Cobb, CA
  11. 1.5 4km NW of The Geysers, CA
  12. 1.6 7km W of Cobb, CA
  13. 1.6 12km ESE of Hidden Valley Lake, CA
  14. 2.8 2km N of The Geysers, CA
  15. 2.5 4km NW of The Geysers, CA

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

For this area

The largest earthquake within 50 km in our catalogue was M 5.0 on 2016-12-14 — it released about 130 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.